Air-heater for automobile torpedoes.



P. M. LBAVITT. AIR HBATER FOR AUTOMOBILE TORPEDOBS.

I APPLICATION FILED JUNE 7, 1907.

Patented Mar. 1, 1910.

,INVENTOR Application filed June 7, 1907. Serial No. 377,706.

. Heaters for Automobile ple.

\ nnrrnn srarns Parana orator.

manic M. LEAVITT, orNEw YORK, N. Y.,

assrenoa re a. w. Brass comma, or

BROOKLYN, YORK, A CORPORATION OF WEST VIRGINIA.

AIR-HEATER roe AUTOMOBILE roarnnons.

To all whom it may concern:

Be it known that I, FRANK M. LEAVITT, a citizen of the United States, residing in the borough of Brooklyn, county of Kings, city and State of New York, have invented certain new and useful Improvements, in Air the following is a specification.

This invention in means for heating the compressed air in an automobile torpedo in order to increase the energy which is imparted to the propel- 1mg engine pedo either a greater speed or the ability to travel over a longer range.

Heretofore the air heater has been applied either within-the compressed air reser- VOlI', or exterior thereto and between the redueing valve and the engine. Each of these arrangements has its own advantages and disadvantages. My present invention provides means whereby I aim to secure the ad vantages of both methods without. involving the disadvantages peculiar to either.

When the air is heated within the reservoir or fiask the temperature impartedtothe air is lowered upon the passage of the air through the reducing valve, so that the temperature is materially reduced before the air reaches the engine, and part of the added.

efficiency imparted by heating is lost. When the heater is placed beyond the reducing valve the air arrives at the engine with practically the same heat imparted to it in the heater, so that a greater amount of' work may be obtained from a given weight of air. There is alsothe advantage that the hot gases do not pass through the torpedo valve system. But this external hcatin involves a serious loss,.whieh is saved by placing the heater within the flask; namely, that the heat is not utilized to expel so much of the stored air toward the end of the run, so that with this system there remains a larger residue of eompressed'air unutilizcd after the run is over. This last condition may be best understood by considering a typical exam- Assumethatthc air flask or reservoir when charged'to full pressure (2250 pounds) will hold 191 pounds weight of air; and that the pressure is diminished by the reducing valve to 300 pounds per square inch as the working pressure delivered to the eng ne. Now Whenthepressure m the flask falls to-' ward the end of the run to 300 pounds the Torpedoe's, I of whiclr provides an improvement and thereby .impart to the 'tor-' Specification of Letters Patent.

have been. utilized. If

' so that 174 sible for effective utilization.

Patented Main 1, 1910.

run is pralrlcrtieally over, because to continue it with a di nishmg pressure and correspond ingly diminishing speed would be impractical. Where the air. is not; heated within the flaskthe work done in causes that which remains to radua y'grow colder, so that at the end of t e run its temperature is frequently below zero; in. pract1ce.it ,is found that with a final 800 pounds at the gage, if the the air pressure rises to about 500 Under these, conditions of the weight of air, only 148%,} pounds on the other hand the air is heated within the flask its final chilling is avoided, and sutlicient heat can be imparted to it to expel considerably more air than if the temperature in the fiaslercmained unchanged; in practice it is--.found that by heating the air to nearl .600 degrees Fahrenheit, if the pressure at t s end 0? the run is 300 ounds, then after coolin to'the normal it fills to about .200 pounds, caving only say 17 pounds weight of air in the flask,

ounds of air have been used to produce useiill work, as against 148% pounds in the case where the air was not heated in the flask.

By my invention in order to combine the advantages of both systems I provide an outside heater located beyond the reducing valve, combined with means for heating the air in the flask toward the end of the run. The function of the latter heating means is not primarily to directly increase the efficiency of the air, outside heater; but is to expel the maximum weight of airfrom the flask and thereby deliver as much of the storedaip energy as pos- The heater within the flask might operate from beginning to end of the run, but as its function is not required during the early part of the run I prefer to confine its operation to the latter portion of the run. Preferably I provide pounds. original for starting the combustion in this heater when the pressure in the flask has fallen to about 500 or 600 pounds.

The accompanying drawings show-a suitable and preferred embodiment of my invention.

Figure 1 is a vertical longitudinal section of an intermediate portion of a torpedo,

. showing part of the air reservoir, the engine, I

expellinglthe air ressnre of ask stands long enough to reabsorb the heat lost during "the run,

as this is performed by the i the heater within the reservoir and the igary 25, 1902.

hits!" therefor.

Referring to the drawings, letA designate the shell or hull of the torpedo, B the compressed air reservoir or airflask, C'the en-v gine or motor, here shown as a turbine, D

the propeller shaft, E the air heater or combustlon chamber (familiarl called the superheater and F the'fue -pot or vessel in which. the liquid combustible is stored. Compressed air passes from the reservoir to the engine by means of a pipe a controlled by a starting 'valve G and leading thence to a reducing valve H from which the air at reduced pressure passes through a pipe I) to the heater E, and thence by a pipe to the inlet or nozzle of the engine or turbine. In order to feed the alcohol or other liquid fuel from the vessel F into the heater E, a

branch pipe d is arranged to take air from the pipe b and lead it into the top of the vessel, while from the bottom of the vessel a fuel pipe e leads to the fuel nozzle or atomizer f. A choke-valve 9 may be provided to insure that the air ressure atd shall be sutliciently in excess of that in E to cause a flowof the liquid fuel. Any suitable igniter h is provided to start the combustion in the heater E.

The parts thus described are already known, and form no novel part of thepresent invention.

According to this invention a supple mental heater J is provided within the reservoir B, and a secondary igniter K is 3.1 1 ranged to start the combustion in this heater at a suitable time, preferably toward theend of the run. The heater J and igniter K may be variously constructed. A suitable construction is that shown, which is similar to that set forth in my United States Patent No. 693,872, granted Febru- The heater J is best made as a receptacle sutliciently open at the top, and which can be charged with a sufficient quantity of liquid fuel, as shown at i. The igniter K is or may be of precisely the construction set forth in my aforesaid patent, except that its proportions are so modified that its action is delayed. so that instead of operating immediately after the starting of the engine it does not operate until toward the latter part of the run. Tn the construction shown a slow-burnin cartridge 1 having a percussion cap 2 1s ignited by the striking of this cap by a tiring-pin 3, which pin has a head 4 and is pressed down by a strong spring ;\t starting, it is held back by a PltijtCillOllii engaging the head 4, which pro ection is formed on a plunger 7 which may freely slide in a cylindrical chamber formed in a shell 8. The )lunger is pressed down by a spring 9, and is lifted engine, as shown.

to release the firin -pin by the movement of a plunger 10 whic slides freely in a cy1indrical chamber 11 and has'a stem 12 passing up through a partition 13 into contact with the bottom of the plunger 7. The cylindrical chamber 11 communicates beneath the (plunger 10 by a pipe '14 with the compresse air on the outlet side of the reducing valve H and preferably with the pipe at ornear the nozzle or inlet of the The upper side of the chamber 11 communicates by a pipe 15 with the outer air. The shell 8 communicates through a tube 16 or otherwise with the compressed air in the reservoir B, and by reason of the loose fit of the lunger' 7 this air pressure reaches the hea 17 of the stem 1E2, which head forms a valve which is ground to a seat in the partition 13. Consequently the high air pressure in the reservoir presses downwardly upon the-valve 17, whlle the reduced air pressure which reaches the engine. presses upwardly beneath the plunger 10; so long as the reservoir pressure remains high enough to hold down the plunger against the uniform ressure tending to lift it, the igniter remains passive; but when the/reservoir pressure falls to a predetermined point (determined by the relative areas of the valve 17 and plunger 10) the downward pressure on the valve 17 becomes insufficient. to resist the upward pressure on the plunger 10, and the latter consequently is forced up, so that it lifts the plunger 7, withdraws the projection 6, and releases the firing-pin, which is thrown downward by its springnnd explodes the cartridge, thereby igniting the combustible in the heater J. For example, with a pressure of 300 pounds in the pipe 14, if it be desired that the igniter shall act when the ressure in the reservoir falls to 600 poun s, it is only-necessary to make the valve 17 of an area onehalf that of the plunger 10. Suflicient li uid fuel is placed in the heater J so that w en ignited towagd the end of the run it will continue to burn until at or about the termination of the run.

While the construction described is believed to he the most simple, yet it is apparent that it may be greatly modified without departing from the present invention. For 7 example, the secondary igniter K may be greatly changed. This igniter may be operated from the engine in such manner as to insure its operation at the proper time; for example, it may be thus operated by the means set forth in in application for U nil ed States patent file February 16, 1907, Serial No. 357,629. It is referable but not essential that the heater be operated only toward the end of the run; instead of this its ignition might be effected in the early part of the run, but in. such case it is preferable that the combustion should be mainin its passage from the reservoir to the enof the run to expel a greater "portion of the seam;

tained at a slow rate during the early por- I tion of the run, and be augmented toward l the latter portion. v I claim as my invention p 1. In an automobile torpedo, a compressed air reservoir, an engine, an intervening rei ducing valve, and means beyond said valve for heating the air under reduced pressure in its passage from the reservoir to the engine, combined with means for heating the air in the reservoir during the latter por- 2. In an automobile torpedo, a compressed air reservoir, an engine, an intervening reducing valve, andmeans beyond said valve forheating' the air under reduced pressure gine, combined With a heater in the reservoir and means controlling it to heat the air in the reservoir during the latter portion only residual air.

3. In an automobile torpedo, a compressed air reservoir, an engine, and means for heating the air in its passage from the reservoir tothe engine, combined With a heater in the reservoir,- and an ignitertherefor adapted to operate toward the latter part of the run whereby to heat and expel a greater portion ofthe residual air.

i. In an automobile torpedo, a compressed air reservoir, an engine, an' intervening re ducing valve, and means for heating the air in its passage from said valve to the engine, 1

combined with a heateninthe reservoir,' a11d an igniter therefor adapted to operate when the pressure in the reservoir falls to a pre- 1 determined ratio to the pressure beyond the reducing valve.

5. .In anautomobile torpedo, a compressed air reservoir, an engine, an intervening reducing valve, a heater between said valve and the engine, adapted to operate throughout the run,'and a heater in the reservoir adapted to heat the air during the latter portion of the run.

6. In an automobile torpedo, a compressed air reservoir, an engine, an intervening reducing valve, a heater between said valve and the enginehaving'an igniter and 'fuelfeeding means adapted to maintain combustion throughout the run, combined with a heater in the reservoir and an ignitertherefor operatingtoward the latter part of the run Wherebyto heat and expel a greater portion of the residual air.

7. In an automobile torpedo, a compressed air reservoir, an engine, an intervening re; ducing valve, a heater between said valve and the engine, and an independent heater within the reservoir.

In Witness whereofil have hereunto signed my name in the presence of two subscribing Witnesses.

FRANK M. LEAVITT. 

